Hard to see where the exact starting zone was. Either triggered by cornice fall or more likely just overloading of the weak faceted snow on the steep east facing slope. East facing slopes in the area were mostly fist hard loose grain facets to the ground with the storm snow on top.
Also noted new snow slides on steep south facing slopes on Bald Mountain. Due to flat light photos did not turn out. Probably instigated from solar affect on Monday.